Background An important aspect of a new surgical technique is whether it can be performed by other surgeons in other institutions. The authors report the first 297 cases in a multi-institutional and multinational review of laparoscopic cholecystectomy performed via a single portal of entry. Methods Data were collected retrospectively for the initial patients undergoing single-port cholecystectomy by 13 surgeons who performed these procedures in their institutions after training by the authors. The review included operative time, blood loss, incision length, length of hospital stay (LOS), necessary additional trocars, and other parameters important to cholecystectomy. A database of all the single-port-access (SPA) surgeries performed by the surgeons included demographic and procedural details, LOS, complications, and initial follow-up data. Results To date, 297 single-port cholecystectomies have been performed for a variety of diagnoses, primarily cholelithiasis. The average operative time was 71 min, and the average LOS was 1-2 days. The average blood loss was minimal. The use of additional port sites outside the umbilicus occurred in 34 of the cases. Of the 35 intraoperative cholangiograms performed, 34 were successful. No significant complications occurred except for seromas and minor postoperative wound infections. These results are comparable with those for standard multiport cholecystectomy. In addition, no access site hernias (ASH) occurred. SPATM is a Trademark

Xenon difluoride (XeF2) reacts with methanol to form an unstable reactive species CHgOXeF (1). Formaldehyde is produced quantitatively by disproportionation in the absence of unsaturated hydrocarbons or with unreactive alkenes. Hydrogen fluoride generated in situ complexes with 1 to form 2 which reacts with unsaturated hydrocarbons of intermediajte reactivity such as cisor trtms-l-phenylpropene (5c, 5t), indene (6), 2,3-dimethyl-l,3-butadiene (7), and norbornene (8) as an apparent fluorine electrophile and Markovnikov fluoromethoxy products are found.Reaction of XeF2 with methanol in the presence of boron trifluoride as catalyst forms the complex 3 which disproportionates to formaldehyde. Intermediate 3 reacts with unsaturated hydrocarbons of intermediate reactivity (5c, 5t, 6, 7, and 8) as a positive oxygen electrophile to give anti-Markovnikov fluoromethoxy products. However, very reactive (electron rich) alkenes such as dihydropyran ( 9) react rapidly with XeF2 to give a carbocation species before the intermediate 1 (or its complex 2 or 3) can be formed.Recently1® we reported on the methanolysis of xenon

Xenon difluoride (XeF,) reacts with alcohols t o form unstable alkoxyxenon fluoride intermediates (ROXeF). The regio-and stereo-chemistry of products from reaction of ROXeF with indene were determined. Alkoxyxenon fluorides [R = CH3, (CH,),CH, and (CH,),C] react as positive oxygen electrophiles (OE) when boron trifluoride-ether is used as catalyst. However, these alkoxyxenon fluorides react as apparent fluorine electrophiles (FE) with proton catalyst (hydrogen fluoride generated in situ). Reactions of XeF, and alcohols with electron-withdrawing substituents give alkoxyxenon fluorides which add to indene as an OE species even though boron trifluoride-ether was not used as catalyst. Reactions of XeF, with polynitroaliphatic alcohols and indene give rapid polymerization of indene rather than alkoxyfluorination.

No abstract

Thirty-seven patients with gallstone pancreatitis were encountered over a 28-month period from June 1990 to October 1992. The use of laparoscopic cholecystectomy with intraoperative cholangiography in the management of gallstone pancreatitis was retrospectively studied. Thirty-two women and 5 men ranged in age from 16 to 74 years. Admitting amylase levels ranged from 241 to 5547 IU/L. No patient had a clinical history consistent with other causes of pancreatitis. Initial treatment consisted of bowel rest until amylase levels had normalized and abdominal tenderness had resolved. Twenty-nine of 37 patients were initially treated laparoscopically, but 7 required conversion to open cholecystectomy. Choledocholithiasis was identified intraoperatively in 4 patients. These stones were cleared either laparoscopically (2), by open common bile duct exploration (1), or by postoperative endoscopic retrograde cholangiopancreatography (1). Patients treated laparoscopically had a median postoperative discharge time of 1.0 day vs 3.5 days for those treated by open technique. Not all patients with gallstone pancreatitis can be treated successfully using laparoscopic techniques. As the experience and confidence of surgeons increases, laparoscopic management of gallstone pancreatitis is appropriate, with open conversion as necessary.